Five of FORT aquatic scientists’ projects focus on the conservation and management of fisheries. The first investigates the effects of barriers on fish movements in the Great Plains streams. The decline of many Plains fishes is attributed to habitat fragmentation of rivers that impedes movement and limits juvenile recruitment (Walters and Zuellig). This hypothesis has been difficult to test, due to the challenge of tracking small fishes in large systems. FORT scientists tracked movement of Flathead Chub in a Colorado plains stream and found that small fish do migrate upstream to spawn. These movements are effectively blocked by small diversion structures common throughout the plains and western United States. Unique fish assemblages of the Great Plains are increasingly imperiled owing to fragmented and exploited river systems.
|The Green River with a barrier to fish movement.
Team members of the Aquatics Sciences Branch (ASB) are participating in Rapid Ecoregional Assessments focused on the status and trends of imperiled fishes. These assessments are providing spatially-explicit analyses for imperiled fishes as part of a Bureau of Land Management initiative for the western United States. Assessments are complete for Cutthroat Trout and Arkansas River Shiner which are respectively found in the Wyoming Basin and the Southern Great Plains ecoregions respectively (Roberts). Products include summaries of the ecology of these species, identification of potential threats and locations of conservation hot spots. Another study investigates how invasive fishes impact native fishes through competition, predation, and genetic swamping (Walters).
FORT ASB researchers are also investigating the effects of river hydromodification on fishes at the National scale (Grantham). Hydrologic and biological monitoring data from national sampling sites are being analyzed to quantify the regional sensitivity of fishes to flow alteration from dams and landscape modification. Lastly, ASB researchers are involved with the development of Adaptive Management Decision Support Systems for Improved 2-D Aquatic Habitat Modeling and Water Management (Hanson and Holmquist-Johnson). This research focuses on communicating integrated spatially explicit physical habitat suitability for multiple flow alternatives to resource managers and stakeholders. Conservation and management of fisheries is an important area of study encompassing many species of conservation and economic concern.
To read more about fisheries studies, please click on the links in the gray box at the right.